Airplane



AIRPLANE Filed May 12 1922 12 Sheets-Sheet l M 'Q6 me M@ HL th 30 mill ilu R. F. HALL May 19, 1925.

AIRPLANE Filed May l2 1922 12 Sheets-Sheet 2 R. F. HALLv AIRPLANE Filed May' 12. 1922 May 19., `1925.

12 Sheets-Sheet 5 May 19, 1925.

R. F. HALL AIRPLANE (Uro: ne

May 19, 1925.

R. F. HALL AIR-PLANE v 3 nvm/1191 K .f7/yall,

May 19, 1925.

R. F. YHALLy AIRPLANE 12 sheets-sheet 1 Filed May 12, 1922 R. F. HALL May 19,1925.

AIRPLANE Filed May 12, 1922 v' 12 Shets-Sheet' B May 19, 192s.. y 1,538,800

` R. F. HALL AIRPLANE Filed May 12, 1922 12 Sheets-Sheet 9 @Ua/wrm@ u May 19, 1925.

. `1,538,800 R, F. HALL.

AInPLANE Filled may 12, 1922 12 sheets-sheet 1o 'www l May 19, 1925. v

1 R. F. HALL v AIRPLANB Fiied May 12. 1922 12 sheets-sheet' 11 May 19, 1925. 1,538,800 R. F. HALL x Y AIRPLANE Filed May 12, '1922- 12 sheets-sheet" 12 wvcno@ 7g4 7gg mdd/shiny@ Cil.

A In the pusher vporting the tail unit Yveiiltion from among` various other oi" booms extending structure with the Patented May 119, 1925.

UNITED-STATES PATENT OFFICE. l

i A e y RANDOLPH F. HALL, OF ITHACA, NEW YORK, ASSIGNOR 0F ONE-FOURTH TO THEO- DORE P. HALL, 0F WALLINGFORD, C0 PAUL WILSON, 0F ITHACA, NEW YORK.

NNECTICU'I, AND THREE-,SIXTEENTHS TO -AIRPLAN E.

, i Application filed May 12, 1922. Serial No. 560,384. l 'J To all fio/1.0m t may concern; f

Be itknown thatl, RANDOLPH l?. HALL, a citizen of the United Statesl of America, and a resident of Ithaca, county of Tompkins, State Of New York, have invented cer-y tain new and usefullmprovements in Airplanes, of whichthe following is a specifif cation.`

vThis invention relates to .certain improvements in.airplanes;' and the nature and objectsof the invention will be readily linderstood and appreciated by those skilled in the arts involved in the light of the following explanation and Vdescription of the vaccompanying drawings `illustrating what I at present consider to 'be tl'ie preferred embodi* men-ts Or` mechanical expressions of the informs, arrangements, combinations and constiucf ltions within the spirit and scope thereof.

The-present invention has reference to 'those types and designs of airplanes provided with tail unit or empennage supporting outriggers, and isi-particularly directed to airplanes of the pusher use Otan Oiitrigged tail unit or empennage. typeslof airplanes, and par; ticularly in those designs in.` which a pusher propeller is mounted along the longitudinal ceiitei of the airplane to the rear of the Wings or supporting surface it is necessary to provide anfnoutrigger structureA for supor empennage atthe properl position with respect to,-and the revquired distance from the rear of themain airplane structure (wings, body and under- 'carriage At present,in accordance with the prevailing design practice, the known tail u1ii|t`or empennage supportin Outrigger structures in, use are characteiji? by a. `strucmre formed of spaced spars or booms extending .rearwardly a 'distance from the main Vairplane structure withl the tail unit or e'inpennage mountedand supported On fthe rear extended lengthsof the spars or booms at the required distance from and inthe proper position and alineinent with respect to the main airplane structure. These spars fromthe main airplane tail 'unit or empennage mounted on the rear lengths thereofare pro vided with suitable exterior bracingdi'sposed.

types requiring the tically -poiii-ts above the generally theaoutrigger spa-rs or sboonis.

iii. substantially vertical and horizontal planes, respectively, between and connecting the spars or booms with the main airplane structure, in Orderfto care for and transmit the vertical and yhorizontal loads and' str sses t'o which these Outrigger spars or boom are subjected bythe tail surfaces or empennage mounted and supported thereon. This Outrigger bracing takes `the form of exterior braces which are inclined forwardly from the outer rear lengths of the Outrigger spars orbooms and entend in vertically and hori- 'zontally disposed planes, respectively, to the The, exteriorbracing for the Outrigger spars or, booms, against vertically acting `loads and v,stresses imposedby theV tail unit or empennage mounted thereon, must extend in substantially vertically. 'disposedv planes y,from 'thesespars or booms adjacent to the empennage mounted thereon, to points verally accomplished 'by providing braces in# clined upwardlyfand forwardly from the rear or Outer lengths ofthe Outrigger spars to the wing structure of the airplane at substantially harizoiitallydisposed planes of the Outrigger spars, and by providing similar braces inglined down-- wardly and forwardly from the spars to points ontlie wings or undercarriage below Thus, tlienupwardly extending, vertically disposed braces areunder' tension and care for downwardly .ac-ting vertical loads and stresses imposed and distributing the vertical empennage and, A Outrigger loads to the main airplane struc-l distant therefrom. `This' is gener- 'bythe tailunit or empennage,

ture. The Outrigger spar'loracing against horizontally acting loads imposed on the Outrigger structure by the tail unit or empennage mounted thereon, are cared for by providing suitable horizontally disposed exterior braces between and extending from opposite sides of the yOutrigger structureto proper points on the airplane structure proper, usually to points on Opposite wings.

The foregoing general arrangement of outrigger bracing against the loads and stresses im d by the tail uni-t or empennage mounted and supported thereon `is varied. and presented in different manners, but the fundamental and essential requirements and principles are present in the various arrangements of such bracing, to wit, the vertically disposedl and forwardly extending exterior bracing from the outer, rear lengthsof the spars or booms, and the exterior horizontally disposed bracing.

These tail unit or empennage supporting outriggers embodying the `foregoing general characteristics, present structures which possess inherently high head or parasite rcsistance and low aerodynamic eiiiciency, due to the large extent of exterior exposed resistance creating surfaces formed by the Outrigger spars or booms and the exterior bracing therefor. One of the fundamental, contributing causes toA the relatively 'low aerodynamic eiiiciency of certain types of pusher airplanes, is due to the necessity of providing an Outrigger structure for supporting the tail unit or empennage, with the resulting high parasite resistance and generallowering of the performance of such airplanes. Further, the necessity in such Outrigger structures of vertically bracing the spars or booms thereof against vertically acting loads and stresses imposed thereon has limited these Outrigger structures to use and mounting on. and in connection with the multiplane types of airplanes. in order to secure the necessary extent of structure in the airy plane proper, above and below the horizontally disposed planes of the Outrigger spars or booms `to which the vertically and forwardly extending Outrigger bracing can be secured to properly care for the vertically acting loads and stresses to lwhich the Outrigger structure is subjected. For the above,

and certain other reasons. the usecofthe monoplane type with its relatively`higli aerodynamic efiiciency over vrnultiplane types, has been diicult in those types of pusher airplanes, as well as other types of airplanes, inl which or empeniiage is required.

. Therefore, one of the fundamental objects of the present invention is to provide a design, construction and mounting of tail unitor empennage supporting Outrigger materially and effectively the -outrigged tail unit i structure in which-the high parasite or head resistance inherent in the prevailing types of Outrigger structures at present in use, is reduced to the minimum possible by the elimination of the exterior exposed. Outrigger bracing and by the provision of an Outrigger structure of exceedingly clean design with minimum Weight, but relatively high factor of safety; and furtherto provide such an Outrigger structure which, while equally adapted to inultiplane types, is also applicable tol and particularly eflicient with airplanes of the monoplane types, `thus permitting the use of the monoplane in pusher or other types requiring an outrigged tail unit or einpennage, with the resulting aerodynamical advantages from the use of 'the monoplane type. t

A further 'Object of the invention is to provide an empemiage supporting Outrigger structure composed of spaced internally braced girders secured and attached at the I forward ends thereof to the main wing truss of an internally trussed wing and extending rearwardly therefrom with a tail unit Or empennage mounted On the outer-lengths thereof, the arrangement and construction of the girders being such that the vertical and horizontal loads 4imposed thereon are transmitted to and distributed along the main wing truss to which they are secured with- Aout the necessity of providing exterior bracing between the girders and the main airplane structure of wliichthe wing forms an element.

' 'A further object of the invention is to provide an improved design and construction of pusher airplane of the monoplane type embodying the principles of the tail unit or empennage supporting Outrigger features of the invention; the main characteristics ot which design of pusher monoplane are; the mounting and construction of the wing with detachable outer panels secured toa center section or panel; the detachable mounting of the Outrigger structure to the center panel without the use of exposed exteriorbracing; the mounting of the tail unit or empennage on the Outrigger structure in such a manner that the alinement'ofthe empennave surfaces will not be materially atfeted the nacelle on anddetachablysecured to the 'center panel ofthe wing and the attaining of maximum vision. and of range of armament fire whenused for military purposes,

from the nacelle; the mounting and arrangement' of the power plant within the nacelle and driving a pusher propeller;f and `the general design and arrangement of major elements to secure inherent stability, ministructure; the construction and mounting of mum head Or parasite resistance and slipstream interference from exposed parts, and a relatively high general performance and manoeuverability in an alrplane of th pusher type, or other type requiring theuse ofgan Outrigged empennage.

A still further aim and Obiect of the invention is -to provide an embodiment therefof of all metal construction in which thel `main features and characteristics Of the 1nvention are incorporated and presented; and further to-providebcertain novel improvements in the metal construction which are applicable generally to all metal airplane construction, particularly with respect -to` in the aeronautical art, the invention con-4 sists in certain novel features in airplane deslgn and in constructions and arrangements of parts, as will be more fully and specifically referred to and pointed out hereinouter end of the center panel of the 4wing feo larra after.

Referring'to the accompanying drawings :A in top plan Of-` an all.

Fig. y1 is a view` Y metal monoplane design of the pusher type embodying the features ofthe present invention. Fig.-2 is a View in front elevation.

ig. 3 Ais a View in side elevation.

F EFig. 4 is a top plan View of an Outer end' portion ofthe center panel of the wingyand of one of the Outrigger girders mounted thereon and attached thereto, the skin being removed from the lcenter panel and the girderfto show the construction and-arrangement thereof, particularly the construction and arrangement of the built-in truss of the center panel to which the Outrigger girder is attached; a portion of an outer Wing panel being also shown detachably mounted in position o n the center' panel.

'Fig'. 5 is 4a view in side elevation of an andthe built-in girder attaching truss forming 'a part thereof, and ofv an Outrigger girder mounted on the center panel and ,at--

tach'ed to the built-in truss thereof, the skin bein removedsto show the construction and gement. of theoutrigger girder.

Fig. l6 is a top plan view of a portion of .one of ythe outer detachable wing panels, a part of the skin being removed to show the- 'construction -and arrangement of -wing A girder's. p l Fig. 14 is a detall View, in side elevationframe and internal bracing therefor; and -a lpartof the metal skin therefor being shown applied thereon and secured thereto.

Fig. is a transverse vertical section through the main longitudinal truss of one of the outer wing panels, showing the construction Of truss beams Withthe interbracing therefor, and also showing upper and lower contour formers and the manner of `to mounting and securing the same over an the main wing'truss beams, the leading and trailing edge portions of the contour formers not being shown.

Fig. 8 is a transverse Vertical section` through one of the Outer Wing panels.4

Fig. 9 is a detail vertical, longitudinal section through a portion of one of the outer wing panels ^With the skin removed and taken forwardly of the front wing truss beam; the contour formers being vshown 'partly in section and being shown inelevation.

Fig. 10 is a detail perspective view of the inner end of an Outriggergirder and of a portion ofthe rear end of one of the builtin trusses of the center wing panel'to which the Outrigger girder is mounted and at-v tached; showing the girder Aand built-in wing panel truss detached in relative pOsi-' tion for mounting, i struction and arrangement for detachably connecting and mounting the Outrigger girders to the center panel.

Fig. 11 is a-detail view in side elevation of the construction and arrangement of the Lfittings for detachably mounting the Outer wing panels tothe center wing panel, portions of the upper longitudina-ls ofa main truss beam of the center panel and ofan outer wing panel being shown.

and showingone con-l a portion of the front wing truss beam and interbracing thereof- Fig. 12 is a detailY View in sideelevation of the undercarriage, center-Wing panel and nacelle mounted thereon, with the outer Wing panel detached, and particularly showing the nacelle construction and manner of mounting and securing the same on and to the center paneLtOgether with the cockpit -arrangement and motor mounting Within the nacelle; the nacelle skin and the mounted position of an Outrigger girder being indiy cated in dotted outline.l

Fig. 13 is a top plan ,view of the tail unit .or empennage in mounted vpositionon thel outer rear end of the Outrigger; portions of the Outrigger girders being shown, and a "part of the upper horizontal stabilizerskin being broken away to showf'the construction of the stabilizer frame and the bracing-between the stabilizer and the Outrigger of ,the rear end portion ofc7 girder with the skin removed unit mounted thereon, showing an Outrigger and the tail the relativeposition of the tail :unit with respect to the gir-der, and further showing the position and mounting of the tail skids on the Outrigger giiolers..

y .is a detail, fragmentary `View, in rear elevation o oneof the Outrigger girders and a portion o the tail unit' in mounted position thereon.

Fig. 16 is a View in side elevation, and more or less diagraminatical, showing the manner of mounting the horizontal and ver tical stabilizers, which are shown in dotted outline, and to the outrigger girders, one ot the outi'igger girders being partially shown` in dotted outline.

Fig. 17 is a detail View more. or less diagrammatical, and in side elevation., of the fittings for mounting, and attaching the horizontal and vertical stabilizers oi' the tail unit to the Outrigger girders; the fittings being shown in relative mounted position.

lllig. 18 is-a detail fragmentary view in side elevation or Li-portion ot' thev lower girder longitudinal and the manner of aitaching the girder thereto.

19 is a detail Vertical transverse tion tnrougli the lower grirfler ionvituoinal Fig.

and showing: portions or tue gir er inten bracing and the manner ot attaching the saine.

1in'. 2Q is a more or less dirnraminatical View in side elevation oi a In fies. oiin ot outrigger girder in mounted` position on ywing.

Fig. 21 is a. Vertical section more or less diagrammatically taken on Fig. 20. y

Fig. 22 is a View, more .or less diagraminatioai, o another nianneroY mountingthe preferred form ot outrigger girder to a wing.

ig. 23 is e. detail vrieur in side elevation oi? a modified i'orm of nacelle, showing,l particularly the cockpit arrangement motor disposition and. mounting, together with propeller transmission driven thereby.

24C is a side elevation oiE the design airplane ot the invention equipped with tw pontoons in place ot the underearriage the preferred torni, and showing tne mountn ingr and general arrangement of the trussing therefor.

in iii-agree 25 is a front elevation oii the twin pontoon mounting;- and arrangement shown Theyariouseatures `ofthe invention are presented and descrieel herewith, purely by way ot example', as embodied in a monoplane design of vthe pusher type constructed of metal throughout, but it is to be understood, vas will be readily apparent to those iamiliar with this art, that certain of the main feat urea of the invention are notlimited to use longitudinal interbracini.

the line 2li-21,

lto the rear or trailing in ali-metal construetions, as such features of the invention. are equally applicable and adapted. to use with and embodiment in air planes constructed o any materials, or ot any desired combinations of materials. Further, in the preiieried orin and embodiments of the invention shown and described the various features thereof are applied to a pusher type airplane of inonoplaue design, but the various features ot the invention, and particularly the tail unit or empennage supporting outrigger design, construction and mounting features thereof, are applicable and adapted generally to use with and embodiment in airplanes of the multiplane types in which an outria'ged tail unit or ein-- pennage is required, or is desired.

in the preferred form and example illus- Jirated in the accompanying drawings, the invention is presented as embodied in a nioiioplane ot' the pusher type provided with "'ngle pusher propeller mounted on an airis alongr the longitudinal center of the airplane. 'lhis preferred 'form of the iiiien'rion is illustrated generally in Figs. l to il ot the accompanying drawings, and inhides a monoplane wing or main supportfing,` surface 10, consisting of the center section .or panel 1l, and detachable outer panels 12, Secured to and extendingv from opposite sides and in lateral continuation of the con ter panel rl"ne detachable outer panels 1&3 ot the wing 1() are provided with the usual ailerons 14, and these outer panels 1Q are preterably mounted on and attached to the center panel 11, to form a angle in the wing 10, with the resulting advantages in inherent lateral stability. This dihedral angle in the wing 10 is'clearly indicated in the preferred embodiment of the invention as illustrated in Figs. 2 and il. A. suitable nacelle 15 is detachably mounted on and secured to the center panel 11, along the longitudinal'center of the airplane, and this nacelle 15 extends forwardly from the center panel 11 a n ing edge thereof. The nacelle 15 is exteriorly braced and trussed Afrom the center panel 11 by rigid opposite side struts 16 ex tending downwardly and outwardly and inclined forwardly trom the nacelle 15 to the forward portion of the center section or panel; and by opposite side brace wires or tie rods 17 extending from the same points on opposite sides of the nacelle as the struts 16, outwardly, downwardly and rearwardly portion of the center panel 1i (see particularly Fig. 1).

in undercarriage 18 of the usual or any other suitable or desired type, ismounted below and attached' to the center panel 11 beneath the nacelle 15 and depends downwardly trom the center panel. 1n the present instance,

a pair of if-trusses 19 spaced apart an each dihedral lli the undercarriage 18 com rises i 1,5es,soo

secured at the diverged ends of thel struts forming the same, respectively, to the center panel 11. These V-trusses 19 depend downwardly from the center panel 11 andare in clined outwardly to and terminating a distance below the center panel in the converged ends of the struts `forming the same, respectively. The lower spaced ends of the V-trusses 19 are attached to andpconnected unit or empennage 26 is mounted on and across the spaced 'rear ends of the Outrigger girders25 at the required distance rearwardly from the main supporting surface 10 and back' of `and in line with. the pusher propeller Pfand the slipstreamtherefrom. The tail unit orempennage-26 is mounted at a distance rearwardly from and in such a positionwith respect tothe wing 1() and propeller P, as to secure the required balance and the necessary effect from the empennage surfaces in the Hight and control of the airplane. In the illustrated embodiment, the tail unit or empennage 26 consists of the horizontal stabilizer 27 extending Itransversely across and between. the spacedv rear ends of the utrigger girders 25y and adjustably mounted and attached thereto.

LA balanced elevator 28 is suitably horizon- ,is well known and understood by those` skilled in this art. Vertically disposed diagonal drift bracing 22 is provided between the opposite spaced V-trusses' 19 to strengthen the landing carriage in the usual manner.

A motor M is mounted `in and enclosed by the nacelle 15 and drives a propeller shaft 21 (see Fig. 12), in this instance the motorcrank shaft, which is disposed along the longitudinal center of the nacellel (longitudinal or fore and aftaxis of the airplane) -and extends rearwardly and outwardly beyond the rear end of the nacelle 15. A pusher propeller P is mounted on the outer end length of the shaft 24 to the rear ofthe trailing edge 'of the center panel 11, ot' the lnonoplane wing 10. Due to the position and mounting of the pusher propeller l. along the longitudinal axis of the airplane and to the rear of the wing 10, in

order to properly position and mount the tail unit or empennage at the required distance to the rear of the supporting surface or wing 10, and in the proper position along and with respect to the longitudinalI center of the airplane `to the rear of and in line .with the slipstream of the propeller P, it

is necessaryto provide an Outrigger structure extending rearwardly from the wing 10 and affording the necessary clearance to the propeller P and the minimum slipstream interference from structural elements.

c AXccording to the present invention, the

tall unit or elnpennage supporting out'rlg-v ger structure is formed by spaced substantially horizontally disposed Outrigger girders 25 extending rearwardly'from opposite points in the rear oltrailing portion of the center panel 11, adjacent the outer ends thcrcofl respectively, with the pusher propcller P mounted to the rear ofl thccenter panel, located and extending between the torn-'ard center panel attached end portions of t-he said spaced Outrigger girders. A tail tally pivoted on and along the trailing edge of the horizontal stabilizer 26 and forms a rearward continuationthereof, in the usual manner. The vertical empennage surfaces are double and comprise twin vertical stabilizers 29 attached to the rear ends of the girders '25 along the longitudinal centers.

thereof, respectively, and extending Vertically upward therefrom above the stabilizer I 27. A balanced rudder 30 is vertically pivoted on and alongthe rear trailing edge of each vertical stabilizer, respectively, for lat-- eral horizontal swinging movement thereon, thus providing twin balanced rudders for lateral directional control of the airplane.

The horizontal and vertical stabilizers are integral and are rigidly braced. The vertical stabilizers 29 are laterally braced by the struts 31 extending .from the upper inner sides thereof, respectively, downwardly and inwardly to spaced points on the fixed horizontal stabilizer 27. f The horizontal stabilizer 27 vis braced by opposite under struts 32 extending downwardly, outwardly and forwardly 'from points at' the under side vthereof a distance inwardly from the .out-

rigger girders 25. respectively, to points on the lower rear ends of the Outrigger girders. These under'struts 32 are shown in Fig. 13 of the drawings particularly.,l and are provided with and include any suitable spring or other tension connection (not shown) to reduce the possibility of inducing bending in the stabilizer from unequal deflection of the olltrigge-'rlirders 25. A tail skid 33 is pivotally mounted on the under lower side of the rear end of each Outrigger girder 25,

and the horizontal stabilizer under struts'y32 are preferablymointed on and attached to the Outrigger girders' at or .adjacent the tail skid pivots, respectively. Stream line tie rods 34 -are provided from the horizontal v stabilizer 27, and extend forwardly and outJ i A wardly across the Outrigger girders 25', re-

specti\`-'ely, to the opposite outer panels 12 of thawing 10. However, these rods 34 are not essential to the required strength and detachably secured at their forward ends.

These girders 25 are built up hollow structures covered with a suitable skin and are so constructed andY mounted thatthrough the medium of the internal bracing thereof, all exterior bracing :from the Outrigger structure to the wing is eliminated, and the vertical and horizontal loads and stresses imposed at the outer rear ends thereof by the tail unit or empennage mounted thereon are transmitted therethrough by the girder structure and distributed to the center panel struc-ture. 'lhe design'construction and mounting of these Outrigger girders 25 is referred to and described in detail hereinafter.

The control system for the empennage surfaces includes the usual control cables from'the nacelle and in the present invention, due to the design and construction of the` outrigger girders, these control cables are practically entirely enclosed, with the resulting decrease in parasite resistance over exposed cables, aswell as the elimination of `possible breakage or damage from exterior forces. The elevator 28 isprovided wththe control horns or cranks 35 mounted thereon adjacent the Outrigger girders 25, and the rudders 30 are provided with the cranks or control horns 36, respectively, extending laterally from the op-v-` posits sides thereof. The v.elevator controli cranks 35 are connected to the control cables 3'? which extend forwardly into and through the interior of the Outrigger girders 25; and

cach rudder control crank 36 is connected at the opposite ends with va pair of control cables 38 which extend forwardly into and through the respective girder 25 above which the rudder is mounted., rli'hese various empennage control cables 'extend forwardly through and are'enclosed within the outrigger girders,` to and'tbough the center panel 'il by means of suitable connections vleading to the control levers mounted in the nacelle l5. Ylhus; theempennage con- 'trol cables are protected and the parasite resistance odered thereby n is eliminated, while by the provision of suitable inspection doors in the Outrigger girders 25., the controlgc'ables are readily accessible for inspectionr and repair. x

lllie wing l() is of the semi-cantilever, internally braced type in which exterior bracing is reduced to the minimum, and consists of the center'panel 11 andthe opposite outer manson detachable panels 12.4 ln the embodiment illustrated, the monoplane wing l() includes ama-in longitudinal truss extending trom tip to tip thereof through the center panel il andthe outer detachable panels l2, the portion of the main truss in the center panel being detachably connected and alined with the portions-thereof in the outer panels.

rthis main longitudinal wing truss is formedv of front middle and rear built up truss beams each consisting of upper and lower longitudinals and interbracing connecting and spacing the same. lllhe truss beams so formed are assembled and connected in proper spaced relation by a series of transverse contour formels extending across and secured to the upper and lower trussbeam longitudinals, and interbracing is provided between the 'vertically alined upper and lower contour formers, respectively.. The pairs of upper andlower contour formel-s extend and converge forwardly and rearwardly from the main wing truss to dene the leading and trailing edges, respectively, of the wing. A suitable covering or skin, in the present example corrugated sheet metal, is secured and attached over and to front,'middle and rear truss beams A, B, and

C, respectively, each consisting of the spaced upper and lower tube longitudinale 40 and 41, respectively. The upper and lower longitudinals of each truss beam are interconnected and braced by a series of vertically disposed angle members 42 extending therebetween at spaced intervals therealong; and by a. series of diagonally disposed angle members 43 extending from the upper ends of the braces 42 downwardly and inwardly to the lower lends of the braces 42, respectively, adjacent thereto (see Fig. 9,.

dle truss beam B at the upper ends of the ',lhus, each wing truss beam A, B, and C is built up of the upper and lower longi- J tudinal wing truss. The series of upper conspaced vertical braces 42, forwardly and the interbracing 42 and 43 between the truss rearwardly to the lowerlongitudinals 41 of beam longitudinale, and the inter-bracing 44 the front and rear truss beams A,and B, between thetruss beams. These fittings 50 respectively, at the lower ends of the braces [are provided with various 42 thereof, opposite and in line with the 51 to which the ends ofthe diagonally disposed braces 44, respectively attached,`as by riveting, 'welding or any (see particularly Figs. 6, 7 and 8). other desired manner. The various inter- A series of upper and lower contour bracing 4Q, 43 and 44, are preferably formed formers 45 and 46 are secured transversely of metal angle bars of L-shape in cross secacro'ss and attached to the upper and lower tion as indicated in the drawings. The longitudinals, respectively, of the truss transverse upper and lower contour foi-mers beams A, B and C forming the main longi- 45 and 46, are formed of angle bars L-shaped in cross section and are secured across and tour formers 45 are spaced .apart and atattached to the wing beam longitudinals by tached to the upper longitudinals `of the cutting the verticallydisposed flange theretruss beams, above and inthe same trans-V of and bending opposite portions thereof verse vertical planes with the spaced seriesoutwardly to form openings in the vertical of diagonal braces 44, respectively, extendflange to receive the tube longitudinals,` with ing transverselybetween and connecting the the bent out portions of the'vertical flange truss beams A, B and C. The series of lower forming ears 52 on opposite` sides of the contour formers 46 are spaced apart and at.- longitudinals through which the attaching tached transversely across the lower 'longirivets 53 are extended and secured. Vith tudinals 41 of the truss beams A, B and C, P this manner of mounting the contour directly below, in line with and in the same forn'iers, the horizontally 4disposed flange transverse vertical 'planes as the series of thereof rests upon and across the beam longispaced upper contourv formers and 46, tud'inals and the attaching` rivets 54 are exrespectively. The series of spaced upper and tendeddownwardly through the contour lower contour formers are extended forformers and the tube longitudinals at the wardly and rearwardly beyond the main points they rest thereagainst, thus the conwing trussiand are-curved downwardly and tour formers are rigidly secured and atupwardly, respectively, to converge in a -tached to the truss beam longitudinals by series of spaced points along and forwardly the .horizontally disposed rivets 53 and the of the Wing truss, and in a series of spaced vertically disposed rivets 54 passing therepoints rearwardly of the -wing truss. The` through andbinding the contour foriners l define the line ,of the trailing edge of the' forward converged ends ofthe upper and to the beam longitudinals. In this conneclower contour formers define the line of the tion see particularly Figs. 7 and 9.

leading edge of the wing andare connected The wing lframe so formed and con-` by a longitudinally extending bar 47 `while the series of'rear converged suitable or desired skin, preferably corruends of the upper. and lower contour formers gated sheet 55- as illustrated in Figs. 6 and 8, ofthe accompanying drawings. A series wing and are connected by a longitudinally of spaced, upper and' lower longitudinal extending edge bar 48 (see Figs. 6and` 8). stringere 56 and 57, respectively, arey extend- Thus it willn be apparentfrom the foregoing ed across the upper and lower contour that the spaced series of pairs of upper and formers 45 and 46, longitudinally of the lower contour formers 45 and 46, withA the Wing, and are suitably riveted, welded or diagonal inter-truss beam bracing 44 and-the ofherwise attached thereto (see particularly vertical interbracing betweenthe-upper and Fig. 6).

The corrugated metal sheets 55 lower longitudinals of each truss beam,`pro are placed transversely across, that is, with vides, in effect, a series of transverse ribs the corrugations thereof disposed transextending in and through the wing. Any versely ofthe wing in the directio'nof Hight lugs and platesk interbraeing 1s i leading `edge structed, is covered with and 'enclosed by any suitable or desired driftbracing 49' extend; thereof, and riveted or otherwise secured on 1 ing diagonally' across the cells o-f the wing and to .the longitudinal stringers 56, as

defined by the` spaced contour-formels, is vclearly shown and/indicated `in Fig. 6;, provided between the 'truss beams `of the Transverse binding strips 57 main wing truss in the horizontal planes of. at spaced intervals transversely,4 across and the upper and lower beam longitudinals, re- 'spect1vely,'` (see Fig.' 6). j transverse contour formers 45, and rivets 5S In the all-metal wing construction of the ai'e then placedwm onthe corrugated skin, preferably over the or, other suitable fastening means, are se-. invention, the longitudinals 40 and 41 of the cured through the binding strips, skin 55 wing truss beams A, B and C, respectively, -and stringere therebelow,.to securely bind are formed of suitable metal tubes. Metal and attach the metal skin between the bindttings() are attached around and secured ing strips and the stringersiwhich are att0 the wing beam longitudinals 40 and 41 'tached to the transverse contour formers. at`the proper points to receive the ends of The metal skin 55 1s' secured by rivets' t8 the iongitudinal stringers between the binding strips and tormers l5 therebeneath, in order to iirmly attach and stiden the skin between contour i'oriners. The skin is :further attached by rivets 58 along the line orf the contour iormers i5 and binding strips 57,. transversely oi the Wing. The corrugated sheetsk may be bent over and around the 'leading edge bar 4'?, as indi- Acated in Fig. 8, and entend rearwardly across and @cured to the upper and lower sides of the Wing frame, with the rear edges thereot suitably attached to the wing traine along` the trailing edge thereof.. However, other arrangements ot the metal sheet es utiiized, the feature of particular g the employment ot the longitudiagers 56 and the riveting or other s of". attaching` the metal sheets thererough the medium of the binding strips By the construction and arrangement o' the metallic Wing trame covered with andv enclosed by the corrugated metai skin, a

wing minimum-Weight and skin `friction,

vwith maximum strength is secured in which corrugated metai sheet 55 forming the ereo adds to the ength in absorbcaring; tor cer ci the strains and r. to which the v. subjected, as se apparent to thos ed in this art ifi *c the toregoing description of the Wing construction in the light of the accompanydrawings.

outer Wing panels i2 are detachably mounted on and attached to the opposite ends of the center panel ll. is described hereinbetore, the inain longitudinai Wing truss composed of the interconnected. and interbraced front, middle and rear truss beams la, B and C, extends longitudinally of the Wingspan rom tip to tip, the truss beams bein? suitably tapered toward the r ends to give the desired taper to the in the present embodiment of the ation the main Wing truss comprises tions or units, the portion extending enough the center panel l and the two outer portions extending through the opposite t panels l2,.respectively. ln assembled moon i position of the wing l0 these three sections or units ot the Wing truss are alined and detaehably connected together to form the continuous, unbroken main Wing truss extending longitudinally through the Wing i0. rlhis is accomplished by providing the opposite outer ends of the upper and lower longitudinals it? and 4l, respectiveiy, oi the Wing 'truss beams A, B and Cot the unit section of the main wing truss in the center Af ,fzaanei il, with the socket r'ittings 60, and by providings the inner ends oit the upper and iower lov itudinals i0 and 4l, respectiveiy, o: the ating` truss beams in eachunit ection ot vie main Wingtruss in the outer Wing paneis i2, respectively, with the ball ttings (il Maase@ which are adapted to tit and be detachably secured into the. socket ittings 60,in the ceuter panel section of the wing truss.; Fig. 1l ot the accompanying` drawings illustrates the construction, mounting and relative positions ot these fittings 6G` and 6l for detachably mounting the outer panels 12 ot the Wing to the center panel. 'llhe center panel socket fitting comprises a body Vlength cr sleeve 62 which extends a distance into the end of truss beam longitudinal and s rigidly secured and ixed therein by a series of transverse rivets or bolts 63 extending through the beam longitudinal and the sleeve. rlhe body or sleeve 62 is -provided. With the outer head 64- enteriorly screw threaded and `iormcd with a socket 65 in the outer end thereoi'. The ball fitting 6i which is secured to the inner ends ot the truss beam longitudinale ot the outer panels i2, comprises the body length or sleeve 6G which is extended a distance into the end of a truss beam longitudinal and secured therein by the'transversebolts or rivets 67, in a manner similar to that of the ttings 60. The outer end of the sleeve 66 is termed with a rounded head or bali. on the outer end of the beam longitudinal and a locking; sleeve o9 is loosely mounted and confined on the outer end o the longitudinal by means ci a tls-.nge 7C formed around the inner end oi the rounded or ballhead :58 et the fitting 61. The locking sleeve 69 is ovided with an internally threaded ore which is adapted to receive 'the threaded `head oi the fitting 60, and is also formed with a positioning bore through the medium ci which the dihedral angle at which the outer panels are. mounted on and to the center panel is determined, as clearly vshown in Fig. l1. f

As explained, the outer ends of the center panel truss beam longitudinale are each provided with a socket hitting 60 and the innerv ends of the outer panel truss beam longitudinals are each provided Witha socket tittin 60 and the inner ends of the outer pane truss beam longitudinals are provided with the ball fittings 6i, respectively. The outer panels 12 are detachably mounted on and attached to the center panel l2, by alining and seating; theball fittings 6l. thereof in the respective socket iittings 60 oita the center panel and then screwing the sleeves 69 oi:V the ittings 6i onto the respective threaded heads 64 to draw the outer Wing panel beams into alinement with they center panel beams, with the ball heads 68 tightly seated in the sockets 65 of the center panel ttings 6G, respectively., The angle ot the outer panels l2 to the center panel ll is determined by the angle of the positioning bores in the sleeves 69 to the longitudinal anis of the said sleeves, respectively. Thus the outer panels are quickly and easily attached rigid.-

dit? 

